AB0892 SMOKING DOES NOT REPRESENT A SUSCEPTIBILITY FACTOR FOR THE DEVELOPMENT OF SYSTEMIC SCLEROSIS: AN ANALYSIS OF THE LEIDEN CCISS COHORT
Authors: J. Ciaffi, S. Liem, T. Huizinga, J. De Vries-Bouwstra
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> A proinflammatory and immunosuppressive role of cigarette smoking has been suggested in rheumatic and autoimmune conditions, with former and current smokers having increased susceptibility to the development of several diseases [1]. Conversely, a study from the United States showed that ever-smoking was not associated with a significant risk to develop systemic sclerosis (SSc) [2]. Up to date, no other study addressed smoking as a possible risk factor for developing SSc. <h3>Objectives</h3> The aim of our study was to investigate whether smoking is a risk factor for disease susceptibility in SSc in the Dutch population. <h3>Methods</h3> At Leiden University Medical Center, the prospective Combined Care in Systemic Sclerosis (CCISS) cohort was initiated in 2009 and, as of January 2022, 708 SSc patients have been included. Information about smoking history was collected at time of enrolment in the cohort, allowing patients to be categorized into never-smokers and ever-smokers. Data about smoking habits in the Dutch population from 2014 to 2021, stratified for sex and age (12-25; 25-45; 45-65; &gt;65 years) are accessible from the Dutch Central Bureau of Statistics website (https://opendata.cbs.nl/#/CBS/nl/dataset/ 83385NED/table?dl=6A354). The prevalence of ever-smokers in the CCISS cohort was compared with the prevalence of ever-smokers in the general Dutch population using chi-square tests. Due to the limited number of young SSc patients, only individuals aged 25 or above were included in the analysis. In order not to miss potentially relevant differences attributable to changes in smoking habits during time, two index years were chosen for the current analysis, 2015 and 2021. Age of the SSc patients who were enrolled in the CCISS cohort at the time of the index years was calculated. Patients who had died before each index year were excluded from the relative analysis. Official data about the Dutch population size and age composition were retrieved from the Dutch Central Bureau of Statistics website (https://www.cbs.nl/visualisaties/dashboard-bevolking/bevolkingspiramide). <h3>Results</h3> Details about the population size in each age range and the number of patients included in the study are reported in Table 1. No statistically significant differences emerged in the comparison of ever-smoking rates between SSc patients and the general Dutch population both in men and women and in each of the three age categories (all p-values &gt; 0.05). <h3>Conclusion</h3> Our study demonstrates that the percentage of ever-smoking individuals is comparable in SSc patients and in the Dutch population. Although the stratification might have decreased the statistical power of our analysis, we can conclude that smoking does not confer an increased risk for the development of SSc in the Netherlands. <h3>References</h3> [1]Arnson Y et al. Effects of tobacco smoke on immunity, inflammation and autoimmunity. J Autoimmun 2010. [2]Chaudhary P et al. Cigarette smoking is not a risk factor for systemic sclerosis. Arthritis Rheum 2011. <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.